Conventionally, with respect to an air conditioner which blows conditioned air from an air outlet in order to air-condition an indoor space, there is disclosed an art in which a means for detecting a first temperature of a first space near a ceiling and a means for detecting a second temperature of a second space near a floor are provided, and when a temperature difference between the first temperature and the second temperature becomes greater than or equal to a predetermined value, an operation of stirring air in the space to be air-conditioned is performed (refer to, e.g., Patent Literature 1).